An rc1 should be updating fine to rc2, if you want to upgrade a 8.1.x to the 8.2 rc2 release then the developer will upgrade, but the application server part needs a new servoy_update.zip attached to this post (overwrite the one in your install)

Something must really go wrong in the browser there. Can you open the browser link (that is written out in the workspace log when you open an editor) directly the Internet Explorer and look what the console tells you?

What kind of components should you see there? Did you update your webcomponents, because from 8.2 on the servoy extra or the bootstrap components needs to have newer versions.